Referring to FIG. 1, retail stores typically display pricing information on paper labels located on shelf edges (shelf labels); FIG. 1 shows an example of a typical printed shelf label. Shelf labels are fitted into C-shaped channels at the edge of product display shelves. Typically, an in-store computer-based printing system downloads “Price Files” from a central location, such as a Retail Chain Headquarters. The information in Price Files is printed on shelf labels and these new shelf labels are manually inserted into the shelf C-channels, usually on a weekly basis. A typical large retail store must update thousands of shelf labels each week.
Referring now to FIG. 2, some Electronic Shelf Labels (ESL) 10 have been produced in an effort to automate the shelf labeling process. As shown in FIG. 4, ESLs 10 display basic price information on a segmented liquid crystal display (LCD).
Referring to FIG. 2, ESLs 10 may receive display information by infrared (IR) or radio frequency (RF) communication 12. Current ESLs 10 often use unidirectional communications techniques to transmit data from the in-store computer-based pricing system to the deployed ESLs 10. Some ESLs 10 are capable of bidirectional communication, allowing the deployed ESLs 10 to send information or requests to the in-store computer system 14. Communication between an in-store computer system 14 and the deployed ESLs 10 is facilitated by one or more access points 16. Access points 16 are often located in the ceilings of the store.
Prior art display tags have suffered other limitations, as well. Typical prior art has no ability to provide a display larger than a single shelf-edge device. Likewise, the prior art is unable to provide pricing and Advertising, Marketing and Promotion (“AMP”) in synchronicity and without significant lag time. Still further, existing RFID devices are unable to sense the presence of a customer, nor to communicate information to devices which may be carried by a customer.
Thus there has been a need for an RFID system which resolves the foregoing limitations of the prior art in cost-effective manner.